Oprensning af klorerede opløsningsmidler ved stimuleret reduktiv deklorering - bilagsrapportBilag E Regenesis‘ forslag til substratmængder
9 Bard Avenue Red Hook, NY 12571 9 October 2000 H157d Christian Mossing Via G. Moller; baltecdk@post2.tele.dk Subject: Field Pilot Test for Use of Hydrogen Release Compound (HRC) at the Copenhagen County site (Jægesborg Allé 24 and Trunnevangen 2). Dear Mr. Mossing: We have evaluated the latest information that you provided for the Copenhagen County HRC pilot site. The following sections describe the use of HRC for CH treatment and design information for the proposed HRC field pilot implementation. Additional sections at the end of this proposal discuss performance and delivery issues and recommended monitoring for an HRC program.
Effect of Competing Electron Acceptors on HRC Requirements
Field Testing Program Due to the high concentration of some competing electron acceptors we are recommending the use of HRC Primer in an additional upgradient injection line from the primary HRC treatment injection line. The distance from the installed array of monitoring wells (O1, O2, & O3) and the HRC Primer line should be 3 meters; we have seen upgradeint diffusion of the HRC affects into the wells at closer distances. After the HRC Primer injection line there should be 2 meters to the HRC injection line. The injection points between the two injection rows should form a swatooth pattern. For the pilot test we have assumed the higher velocity of the lower zone of 118m/year. The same HRC/HRC Primer injection rates will be used through the entire treatment thickness. This seems the best approach due to the competing electron acceptor presence. Design parameters for the HRC field test are described below: Christian Mossing-Hedeselkabet HRC Pilot application, Jægersborg Allé 24, Gentofte 9 October 2000 Revision page 2 NOTE: Regenesis foreslår anvendelse af 1.034 kg HRC Primer og 830 kg HRC. Af nedenstående fremgår det imidlertid, at der er byttet om på mængderne, således at der skal injiceres HRC i 5 punkter, svarende til de 1.034 kg og at der skal injiceres primer i 4 punkter svarende til 830 kg.
HRC Delivery to Contaminated Zone Typically, HRC and HRC Primer are applied using direct push hydraulic equipment. Drive rods are pushed to the bottom of the contaminated saturated zone and then HRC is injected as the rods are withdrawn. The minimum recommended rod size is a 0.625-inch (16mm) inner diameter. For sites where direct push is not feasible, auger-based equipment can be used to deliver HRC. Also, the use of permanent, small diameter re-injection wells may be a more cost-effective approach for sites requiring repeated applications of HRC. Technical support personnel at Regenesis are available to discuss the suitability of alternate HRC delivery methods. Costs for HRC injection should be obtained from local subcontractors. If necessary, Regenesis can assist in locating qualified HRC injection subcontractors. Budgetary cost estimates for direct push-based injection range from $1,000 to $2,000US per day. Typically, one to two HRC injection points can be completed per hour and up to 20 points can be completed per day, depending on soil type, depths of injection, and subcontractor experience. HRC should be injected using an appropriate pump capable of processing a material with a viscosity of 20,000 centipoise at flow rates of 11 to 38 liters (3 to 10 gallons) per minute at pressures ranging from 14 bar to 102 bar (200 psig to 1,500 psig). Failure to use appropriate equipment could increase field time and result in improper application of the HRC. Regenesis can provide a suitable pump for a cost of $150US per day plus shipping.
Recommended Groundwater Monitoring Program for Pilot/Full Scale Treatment Monitoring of selected wells should be conducted to validate the HRC-based enhancement of reductive dechlorination processes. Also, an initial or “baseline” round of sampling should be performed to identify pre-HRC installation groundwater conditions. After delivery of the HRC to the subsurface, samples can be collected on a monthly or bi-monthly frequency. After the initial biodegradation and geochemical trends have been identified, the monitoring frequency can be decreased to a quarterly, semiannual, or annual program. Christian Mossing-Hedeselkabet HRC Pilot application, Jægersborg Allé 24, Gentofte 9 October 2000 Revision page 3 The monitoring program should employ low flow groundwater sampling techniques and include the measurement of the following field/chemical parameters:
A specially qualified laboratory should do the analytical testing for the metabolic acids, otherwise most laboratories can provide testing for the remaining parameters. A typical cost for the above testing program is approximately $300US per sample. We appreciate the opportunity to provide this information for your project. Please feel free to call if you have any questions or need more information. I can be reached at 914.758.9243 EST. You can also contact Pen Herring at 949.366.8000 PST. Our email addresses are pen@regenesis.com and dave@regenesis.com. Sincerely, David S. Peterson Applications Engineering Manager cc: Pen Herring, Regenesis |
